Control of multi-position filter mechanism in an optical measuring system
AssigneeBeckman Instruments, Inc.
InventorDavid B. Helphrey
Life of this patent
Estimating the term…
Abstract
A method of identifying an operating position of a multiple-position filter changing mechanism situated in an optical path of a spectrophotometer by detecting and measuring a spectral characteristic(s) of light passed along the optical path to the spectrophotometer detector for one or more operating positions of the filter mechanism and comparing the measured spectral characteristic(s) with stored spectral characteristic information for one or more operating positions of the filter mechanism.
Claims4
For use with an optical measuring system of the type comprising means for directing light along an optical path toward a light detector, the detector adapted to provide a measure of light passed by a sample in the optical path, a plurality of filters, a filter changing mechanism adapted to advance in sequence through a plurality of operating positions to place predetermined ones or combinations or none of the filters in the optical path to attenuate, for each operating position, predetermined selected wavelengths of light passing along the optical path, an improved method of identifying an operating position of the filter changing mechanism comprising the steps of:
- (a) storing spectral characteristic information of one or more of the operating positions of the filter changing mechanism;
- (b) setting the filter changing mechanism in an operating position;
- (c) directing light of predetermined spectral characteristics along the optical path;
- (d) detecting and measuring the spectral characteristic of light reaching the detector;
- and
- (e) comparing the spectral characteristic measured in step (d) with the stored spectral characteristic information in an effort to identify an operating position of the filter changing mechanism.
Dependencies are inferred from the claim text.